JP3733545B2 - Pin type synchronizer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a pin type synchronization device for a transmission.
[0002]
[Prior art]
It is well known in multi-speed ratio transmissions that a synchronization mechanism is used to reduce the shift time of all transmission gear ratios or several transmission gear ratios.
It is also well known that the shift effect required by the vehicle operator, i.e. the force applied to the shift lever, is reduced by using a self-energizing type synchronization mechanism. .
In general, the self-compensating synchronization mechanism is particularly important for heavy trucks because the operator's shifting effect increases with vehicle size.
Prior art examples of synchronizers are shown in US Pat. No. 5,078,244, US Pat. No. 5,092,439, and US Pat. No. 5,339,936, which are referenced in the present invention.
[0003]
[Problems to be solved by the invention]
It is an object of the present invention to provide a pin-type synchronizer with an improved axial retainer for jaw members.
[0004]
[Means for Solving the Problems]
In accordance with the present invention, a pin-type synchronizer as described in US Pat. No. 5,092,439 and described as prior art in claim 1 is selectively operated to frictionally synchronize and A pin-type synchronizer is included that meshes with and is coupled to one of the first and second drives mounted for rotation relative to the axis.
The synchronizer is mounted in correspondence with each of the first and second drives, and the first and second jaw members positioned between the drives and movable in the axial direction are respectively engageable with the first and second jaw members. It has a second jaw member.
The third and fourth jaw members have internal splines that slidably mesh with each other so as to rotate relative to an outer spline formed on the shaft.
First and second cone friction rings are mounted for rotation with each of the first and second drives.
The third and fourth cone friction rings are concentric with the shaft and between the drives to frictionally engage each of the first and second friction rings to provide a synchronous torque to synchronize the drive with the shaft. It is movable in the axial direction.
The radially extending flange has an axially opposite side surface located between the third and fourth jaw members and between the third and fourth friction rings and is applied to the flange The jaw member and the ring are moved in the axial direction in accordance with the shift force (F ₀ ) in both axial directions.
The blocker means is operated when engaged to prevent engagement of the jaw members prior to synchronization. The blocker means has a plurality of pins fixed axially extending between the third and fourth friction rings and in the first set of openings in the flange and spaced circumferentially. is doing.
Each pin has a blocker shoulder engageable with a blocker shoulder formed in a cooperating opening.
The first means is secured to the flange to oppose axial movement with respect to the third and fourth jaw members.
[0005]
The improvement which characterizes the present invention is to constitute first means including a plurality of retainers arranged at intervals in the circumferential direction.
Each retainer includes an axially extending portion disposed in a radially outer portion of the third and fourth jaw members and an axially opposite portion that faces oppositely in the axial direction of the third and fourth jaw members. And a portion extending inward in the radial direction.
Each axially extending portion is axially arranged to slide against the radially inner portions of the third and fourth friction rings to limit the radially outward movement of the retainer. It has a portion that is spaced apart and faces radially outward.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
As used herein, the term “clutch synchronization mechanism” refers to the clutch mechanism used to non-rotatably connect the selection gear to the shaft by the engagement clutch means, ie, the engagement clutch member cooperates with the engagement clutch. This means a clutch mechanism that prevents the engagement of the intended meshing clutch until it is substantially synchronously rotated by the synchronous friction clutch.
“Self-energizing” means a clutch synchronization mechanism having a ramp, cam or the like that increases the engagement force of the synchronization clutch in proportion to the synchronization torque of the friction clutch.
[0007]
Referring to the drawings, a synchronous assembly 10 having a shaft 12 rotatably mounted on a transmission with respect to a gear and axis 12a, axially spaced drives or gears 14, 16, and a double-action synchronizer 22 are shown. Has been.
The shaft 12 has cylindrical surfaces 12b, 12c that rotatably support the gear, and an annular member 12d having an outer peripheral surface with a diameter larger than the diameter of the cylindrical surface.
The annular member has an axial length that separates the gears via shoulders 12e, 12f facing in the axial direction, the shoulders moving the gears closer to each other in the axial direction. Restricted. The movement of the gear in the direction away from each other in the axial direction is limited by a conventionally known method. The annular member is formed by securing a ring to the shaft, or is formed integrally with the shaft as shown.
The outer circumferential surface of the annular member has an outer spline 12g, three grooves 18 having an axial length equal to the axial length of the annular member, and automatic assist lamps 20a, 20b, 20c described below. 20d is formed.
The groove removes several adjacent splines 12g to form an auto-compensation ramp by simple machining.
[0008]
The synchronization mechanism 22 includes friction rings 26 and 28 integrally formed with the gears 14 and 16, jaw members 30 and 32, and inner splines 38 and 40 slidably engaged with outer splines formed on the outer peripheral surface of the annular member 12d. A radially extending shift flange 42 having axially opposite sides 42a, 42b sandwiched between axially opposed surfaces 34a, 36a of the jaw members 34, 36; Three axially extending retainers 44 that secure the flange and jaw members to resist movement, three circumferentially spaced apart, and axially extending from each of the friction members through the flange opening 42c. Annular friction rings 46, 48, and three pre-energizer assemblies, secured to each other by a pin 50 And a (pre-energizer assemblies) 52. The assembly 52 is shown only in FIG.
[0009]
The friction ring has cone friction surfaces 26a, 46a and 28a, 48a and engages the gear to frictionally synchronize with the shaft prior to engagement of the jaw members. The rings 46 and 48 are separated in three circumferential directions, open in the axial direction, elongated in the circumferential direction 46b, 48b, separated in six circumferential directions, opened radially inward, and the friction ring 46, Grooves 46c and 48c extending in the axial direction through 48 are provided. The extra grooves 46c, 48c facilitate the exchangeability of the friction rings 46, 48.
Further, as described below, the grooves 46b, 48b receive the end of the pre-energizer assembly, and the grooves 46c, 48c receive the retainer 44. A wide range of cone angles is used, where a cone angle of 7.5 degrees is used.
Friction surfaces 46a, 48a and / or 26a, 28a are known friction members attached to a base member, as described in U.S. Pat. No. 4,700,833, U.S. Pat. No. 4,844,218 and U.S. Pat. No. 4,778,548. Pyrolytic carbon friction materials are used. These patents are referenced to the present invention.
[0010]
The pin 50 has a large diameter portion 50a having a diameter slightly larger than the flange opening 42c, a reduced diameter portion or groove portion 50b (here, an intermediate portion) disposed between the friction rings 46 and 48, and a plane perpendicular to the pin axis. It has conical blocker shoulders or faces 50c, 50d that extend radially outward from the pin axis and axially away from each other.
When the grooves are disposed within the corresponding flange openings, the fixed friction rings and pins are adapted to effectively engage the chamfered blocker shoulder formed in the flange opening 42c and the blocker shoulder of the pin. Allows limited rotation with the assembly. The pins are fixed to the friction rings 46 and 48 by a conventionally known method.
[0011]
The pre-energizer assembly 52 is a separate pin type, as shown and described in detail in the aforementioned US Pat. No. 5,339,936. Each pre-energizer assembly extends axially between the friction rings 46, 48 through openings 42d that are alternately spaced between the openings 42c.
As shown in FIG. 3, each pre-energizer assembly includes two identical shells 54 and at least two identical leaf springs 56 sandwiched between the shells and biasing away from the shells; There are two retainers 58 for telescopically fitting the entire end portion 56a of the leaf spring, and an oval cup-shaped member 60 disposed in the oval grooves 46b, 48b of the friction rings 46, 48, respectively. .
The oval cup-shaped member 60 and the grooves 46b and 48b extend in the circumferential direction of the friction ring, and have a sufficient diameter in the radial direction of the friction ring so as to allow the opposing end 54a of the shell 54 to slide. is doing.
Each pair of shells 54 has a larger diameter that is smaller than the diameter of the cooperating opening 42d when the semi-annular groove 54b having the chamfered end face 54c and the end 54a are pressed together.
The end portion 54a reacts with the friction rings 46 and 48, and the chamfered portion 54c reacts with the chamfered portion of the opening 42d in the flange 42 corresponding to the initial engagement movement of the flange 42.
The cup-like member 60 provides a firm connection between the friction rings 46, 48 and the end 54a so as to provide a wear resistant material. For example, the cup member is made of steel and the friction ring is made of aluminum or a relatively soft material.
[0012]
As described above, the jaw members 34, 36 have the inner splines 38, 40 that slidably engage with the outer splines 12d attached to the shaft. The outer spline has a flank surface extending parallel to the axis of the shaft, and prevents the rotation of each other by the meshing of the jaw member spline and the shaft flank surface.
[0013]
Further, the flange 42 has stiffener rings 42e and 42f extending in the axial direction from the opposite surface, and automatic reinforcing teeth 62 so as to protrude radially inward into the groove 18 on the outer peripheral surface of the shaft annular member 12d. ing. Each tooth 62 has a self-compensating surface 62a, 62b, 62c, 62d that cooperates or reacts with a corresponding self-compensating ramp surface 20a, 20b, 20c, 20d.
Each stiffener ring has a radially inner surface 42h that receives the annular radially outer surfaces 34c, 36c of the jaw members 34,36.
The stiffener ring reduces axial distortion of the flange 42 during manufacture or use.
The ramp surface allows limited rotation of the flange relative to the jaw members 34, 36 and the shaft 12, increasing the engagement force of the cone clutch initially engaged by the shifting force applied to the flange 42 and supplied by the cone clutch. Counteracting the synchronous torque between the cone clutch and the shaft so as to increase the generated synchronous torque and provide additional axial self-energizing force.
The ramp surface increases the synchronization force in response to torque in either direction so as to increase the synchronization force on one or both gears and / or encounter upshifts and downshifts. .
[0014]
Each of the retainers 44 includes an axially extending portion 44a disposed in a radially outer portion 34b, 36b of the jaw members 34, 36 and an axially opposite surface 34c ', 36c' of the jaw members 34, 36. And has a portion 44b that is spaced apart in the axial direction and extends radially inward.
The retainer extends loosely through the opening 42e in the flange 42 to allow limited relative rotation. Each axially extending portion has an axially spaced radially outwardly facing portion 44c that is received in the grooves 46c, 48c of the friction ring and faces radially inward of the groove. Slide against the part.
The portion 44c is long enough to slide and stay there in the portion facing the inside of the groove.
As shown in FIG. 2, the gears 14, 16 have axially extending grooves 14a, 16a for receiving the ends of the retainer when the jaw members are engaged.
The side portions of the grooves 46c and 48c extending in the radial direction hold the retainer at intervals in the circumferential direction.
The ramp surfaces 20a, 20b attached to the shaft 12 react against the opposing ramp surfaces 62a, 62b of the flange teeth 62 and increase the synchronization rate and / or shift amount of the gear 16 in response to torque in either direction. An additional axial force is created to allow or assist. The ramp surfaces 20c, 20d react with each of the ramp surfaces 62c, 62d and provide an additional axial force to the gear 14 corresponding to the synchronous torque in either direction.
The angle of the ramp surface changes the additional axial force with upshift and downshift, high speed ratio and low speed ratio.
Also, if there is no additional axial force in one direction for one gear or more gears, the ramp surface will be parallel to the axis of the shaft, i.e. no effective ramp surface will be provided.
As explained below, the magnitude or amount of additional axial force is a function of the average radius ratio of the friction clutch and the self-complementing ramp. Accordingly, the magnitude of the force applied by the shift fork to provide the shifting force applied to the shift flange 42 can be varied by changing the ramp angle and / or the average radius ratio.
[0015]
When the flange 42 is in the neutral position of FIG. 1, the reduced diameter portion 50b of the pin 50 is aligned radially with the cooperating flange opening 42c and the friction surface of the cone clutch is positioned slightly spaced apart. The chamfered or angled surface 54c of the pre-energizer 52 acting on the flange opening 42d with the force of the spring 56 is maintained at that spacing.
The axial force generated by the surface of the pre-energizer sufficiently reacts to any additional axial force on the flange due to the self-compensating ramp due to the viscous shear of oil between the surfaces of the cone clutch.
When attempting to connect either gear to the shaft, a suitable shift mechanism (not shown) is connected to the outer periphery of the flange 42 in a well-known manner as shown in U.S. Pat. No. 4,920,815, The flange is moved axially along the axis on the shaft 12 to the left for coupling to the gear 14 or to the right for coupling to the gear 16.
The shift mechanism can be moved manually by an operator via a linkage mechanism, selectively moved by an actuator, or can automatically start the shift mechanism to reduce the amount of force applied by the shift mechanism. Moved by the means to control.
When the shift mechanism is manually moved, it is proportional to the force applied to the shift lever by the operator. Force, whether manually or automatically, is applied axially to the flange 42 and is shown in FIG. 8 by the length of arrow F ₀ .
[0016]
The movement of the flange to the right in the axial direction by the shift force F ₀ of the operator is transmitted to the pin 50 by the pre-energizer surface 54c in order to frictionally engage the cone surface 48a and the cone surface 28a.
As the initial engagement force of the cone surface, the force of the spring 56 and the angle of the pre-energizer surface function.
Initial frictional engagement (asynchronous condition exists and momentarily disables the effect of the self-complementing ramp) ensures limited relative rotation between the flange 42 and the friction ring engaged. Since the cone clutch engaging force and the synchronous torque T ₀ are generated, the movement of the pin diameter-reduced portion 50b with respect to the side surface of the flange opening 42c causes the pin blocker shoulder 50d and the blocker shoulder disposed in the opening 42c to engage.
When the blocker shoulder is engaged, the operator's total shift force F ₀ on the flange 42 is transmitted to the friction ring 48 via the blocker shoulder, so that the cone clutch is at the full force of the operator's shift force F ₀ . Engaged to produce a combined operator synchronization torque T ₀ .
The operator's synchronization torque T ₀ is represented by an arrow T ₀ in FIG.
Since the blocker shoulder is angled with respect to the axial direction of the operator's shift force F ₀ , it opposes the synchronous torque from the cone clutch, but produces an opposite or unblocking torque of less magnitude in the asynchronous state. .
As shown in FIG. 2, when substantial synchronization is reached, the synchronization torque drops below the unblocking torque, so the blocker shoulder moves the pin concentrically with the opening 42c and continues to move the flange axially, Also, the inner spline / jaw 40 of the jaw member 36 and the outer spline / jaw of the jaw member 32 are engaged. The splines / jaws are formed as shown in US Pat. No. 3,265,173 and US Pat. No. 4,246,993. These patents are referenced herein.
[0017]
Even if the effect of the automatic assist lamp is ignored, the cone clutch torque generated by the force F ₀ is expressed by equation (1).
T ₀ −F ₀ R _C μ _C / sin α (1)
here,
R _C = cone friction surface average radius μ _C = cone friction surface friction coefficient α = cone friction surface friction angle
In particular, referring to FIGS. 6 and 7, regarding the operation of the automatic assist lamp, the synchronous torque T ₀ generated by the operator applying the axial shift force F ₀ is transmitted to the flange 42 by the pin 50. It reacts to the shaft 12 so as to cross the self-compensating ramp surface.
When engaged, the self-compensating ramp surface limits the rotation of the flange relative to the shaft 12 and jaw members 34, 36 and flanges the axial force component or additional force F _a in the same direction as the shift force F _0. to act on, the sum of these forces, i.e. the best F _t, furthermore, the total torque T _t of the total additional synchronizing torque T _a in addition to the torque T ₀ is increased as engaging force of the cone clutch.
FIG. 6 shows the position of the auto assist ramp surface when the shift flange 42 is in the neutral position corresponding to the position of FIG.
FIG. 7 shows the position of the ramps and splines when the gear 16 is synchronized by the engagement of the cone surfaces 28a, 48a.
The engaged cone surface generates a synchronous torque in a direction in which the flange ramp surface 62a and the shaft ramp surface 20a are effectively engaged.
Therefore, as shown in FIG. 8, the total axial force for engaging the cone clutch is F ₀ plus F _a, and the total synchronous torque generated by the cone clutch is T ₀ . T _a is added.
When the shift force F ₀ and the synchronization torque T ₀ are given by the operator, the magnitude of the additional axial force is a function of the angle of the self-complementing ramp surface to be engaged.
This angle is sufficient to produce _a sufficiently large additional force Fa to effectively increase the synchronization torque and reduce the synchronization time in response to an optimal shift by the operator.
However, this angle is too low to produce _a controlled axial additional force F _a , that is, a force F _a that increases or decreases in response to an increase or decrease in force F ₀ .
If the ramp angle is too large, the ramp will self-lock rather than self-energizing. Therefore, once the initial engagement of the cone clutch occurs, regardless of the force F _a and the force F ₀ is increased rapidly uncontrollably, driving the cone clutch toward lockup uncontrolled.
Self-locking rather than auto-compensation reduces the shift amount or feeling of shift, overstresses the components of the synchronizer, causes overheating, rapid wear on the cone clutch surface, and shift lever movement by the operator Even disable it.
[0019]
The main variables and equations for calculating the auto assist ramp angle are shown in the aforementioned US Pat. No. 5,092,439.
[0020]
The present invention has been described in the form of a pin-type synchronizer. The scope of the appended claims includes the inventive portion of the disclosed synchronizer, and changes and modifications are intended to be included within the spirit of the invention.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a neutral position of a double-action synchronization mechanism of the present invention.
2 shows the synchronization device of FIG. 1 engaged in the right direction.
3 is a detailed exploded view of parts of the synchronization mechanism of FIG. 1;
FIG. 4 is a detailed view of a shaft portion in FIG. 1;
FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. 4;
6 is an arrow view taken along line 6-6 in FIG. 4 when the shift flange is in a neutral position.
7 is an arrow view taken along line 6-6 in FIG. 4, and is a diagram in which the automatic assist lamp shown in FIG. 3 is engaged.
FIG. 8 graphically represents the axial force and torque acting on the shift flange of the synchronizer.
[Explanation of symbols]
12 Shafts 14 and 16 First and second drives 22 Pin-type synchronizers 26 and 28 First and second cone friction rings 30 and 32 First and second jaw members 34 and 36 Third and fourth jaw members 42 Flange 44 Retainers 46, 48 3rd and 4th cone friction rings 50 pins

Claims (5)

Selectively operated to frictionally synchronize and mesh with one of the first and second drives (14, 16) mounted for rotation relative to the axis (12a) of the shaft (12). A pin type synchronization device (22),
Attached to each of the first and second drives (14, 16) and slidable to rotate relative to an outer spline (12g) located between the drives and attached to the shaft (12) First and second jaw members (30, 32) engageable with each of axially movable third and fourth jaw members (34, 36) having inwardly engaged inner splines (38, 40). );
First and second cone friction rings (26, 28) fixed to rotate with each of the first and second drives, and a first to produce a synchronous torque to synchronize the drive and shaft. And third and fourth cone friction rings (46, 48) that are frictionally engaged with the second friction ring, respectively, and are axially movable between the drives at the same center as the shaft;
A biaxial shift force (F ₀ ) disposed between the third and fourth jaw members (34, 36) and between the third and fourth friction rings (46, 48) and applied to the flange. ) Radially extending flanges (42) having axially opposite sides (42a, 42b) for axially moving the jaw members and rings in response to
Blocker means (50c, 50d) operated when engaged to prevent engagement of jaw members (30, 38 and 32, 40) prior to synchronization, the blocker means being circumferential Are spaced apart from each other, fixed axially extending between the third and fourth friction rings (46, 48), and disposed within the first set of openings (42c) in the flange. Each pin has a blocker shoulder (50c, 50d) engageable with a blocker shoulder formed in a cooperating opening (42c);
First means (44) secured to the flange to oppose axial movement associated with the third and fourth jaw members;
In the pin-type synchronizer provided with
The first means has a plurality of retainers (44) spaced circumferentially, each retainer being disposed on the radially outer portion (34b, 36b) of the third and fourth jaw members. An axially extending portion (44a), and a portion (44b) that is spaced apart in the axial direction and extends radially inward, embedding the oppositely facing portions of the third and fourth jaw members (34, 36). ) And the axially extending portions of each of the radially inner portions (46c, 48c) of the third and fourth friction rings (46, 48) to limit the radially outward movement of the retainer. A pin type synchronizer comprising a portion (44c) arranged so as to be in contact with and slidable in an axial direction and facing radially outward. The part (44c) which is arranged in the axial direction and faces radially outward is engaged with either the first and third (30, 38) or the second and fourth (32, 40) jaw members. 2. A pin-type synchronizer as claimed in claim 1, characterized in that it remains to slide relative to the radially inner portions (46a, 48a) of the third and fourth friction rings when being operated. Each of the third and fourth friction rings (46, 48) has a groove (46c, 48c) that opens radially inward and is spaced apart in the circumferential direction, and a retainer is inserted into the groove. 3. The pin type synchronizer according to claim 1, wherein a retainer extending in the axial direction is slidably received so as to be held apart in the circumferential direction. The third and fourth friction rings (46, 48) are characterized by having grooves (46c, 48c) opened radially inward at least twice as many as the retainers (44) so that they can be exchanged with each other. The pin type synchronizer according to claim 3. The first and second drivers (14, 16) have axially extending grooves (14a, 16a) that receive the ends of the retainer (44) when the jaw members are engaged. Item 5. The pin type synchronization device according to any one of Items 1 to 4.

Images